Testing device for determining mass distribution



Filed June 21, 1940 3 Sheets-Sheet 1 INVENTOR ATTORNEYS 9 3 a h a 4 (4v7 6 m 6 4K 2 i 2 5 0 2 Z 4 w 7 J 8 8 I... m 0 LI m n M E a w J Q i m w oM w H. O. HEM

May 5, 1942.

TESTING DEVICE FOR DETERMINING MASS DISTRIBUTIO Filed June 21, 1940 3Sheets-Sheet 2 A/a/Vaf 0. Hem

-'1 99 94 Intro/.1

, INVENTOR ATTORNEY5 m ZZW H. O. HEM

May 5, 1942.

TESTING DEVICE FOR DETERMINING MASS DISTRIBUTIO Filed June 21, 1940 3Sheets-Sheet 3 Aa/Vof 0. H907 INVENTOR ATTORNEYS Patented May 5, 1942 1TESTING DEVICE FOR DETERMINING MASS DISTRIBUTION Halvor Hem,

Scale Company, New Jersey Toledo, Ohio, assignor to Toledo Toledo; Ohio,a corporation of Application June 21, 1940, Serial No. 341,738

Claims.

This invention relates generally to testing devices, and moreparticularly'to devices-for determining the center of gravity orbalanceor relationship of the weights ofoppositeendsofzeloxh gated objects,such as connecting rods.

The rotating and reciprocating parts ininternal combustion engines, suchas are used for automobiles, airplanes, boats, etc'.,. must/be veryaccurately balanced'to eliminate vibration to the greatest possibleextent. In modernhigh speedl engines a very smalldifference in weight inone of therotating orreciprocating' parts is sufficient to. setupinjurieuswibrations; Variations in weight-or in the locationof thecenter ofmass in connecting rods are particularly responsible for muchvibration in such engines The principal object of thisinvention is theprovision of improved means for determining the distribution of materiali. e., the center of gravity in elongatedarticles such as-connectingrods-in theassortingor the machining ofsucharticles to astandard.

Anotherv object is the provision 1 of improved means. forsimultaneouslytesting both ends of an elongated irregularly shapedarticle.

Another object is the provision of improved means for determining andindicatingdeviations from. a. standard of manufactue for elongatedirregularly shaped articles, such as-connecting rods.

Another object is the provision-of. improved means. in atestingdevicefor supporting each end'of such an elongatedarticle-enaseparate lever and-simultaneously. indicating-the weight ofeach end; and;

A still further. object isthe provision of im proved means-ina'devicezofthe type described for substantially maintaining the distance betweenthe points of pivotal attachment of the ends of an elongated articlesuch. as a connectingrod to independently mounted levers.

These, and-other objects and advantages will be. apparent 'frornthewhich referenceis had to the accompanying drawings, illustrating .apreferred embodiment'of the. invention and :inw'nich similar"reference'numerals refer to similar parts throughout therseveral views.

Inxathe drawings:

Fig. l. is a-front' and. otherr members. being broken away for clarity.

Fig. II is-a=plan"view sectionedisubstantially alongcthesline IL-II ofFig. I.

Fig. 111 is a sectional endelevational viewsectionedzsubstantially.along the lineIlI-III of Fig-:1.

Fig. IV isasectional.endzelevational view substantially' along theline-IV--IV of Fig: I; and,

following description .in'

elevational view of a deviceembodying :the invention, portions'of thehousing 1 balance weight 'means of 1 a nut .fulcrumed by means of apivot Fig. V is an enlarged sectional view substantially along the lineV-V of Fig. I and showing the compensatingv means in greater detail.

Referring to the drawings in detail:

Mounted on a base plate iii, near one ofits ends, is an upwardlyextending. substantially U-shaped fulcrum frame 1 I. The uppeextre1nities of this fulcrum frame are bifurcated and l bearings H arealignably seated upon pins 13 which extend between the arms of thefurcation.

bearings form thesupports for fulcrum pivots M which extendlaterallyfrom a substantially.rectangular portion of a lever i5 (Figs.II and 1).. Extending horizontally from suitable These V ,bosses'in theend of the rectangular portion of the lever lli'are two spaced studsic'which .ad-. ,iustably carry a split-rectangular counterbalance weight.11, the sections being locked together and clamped to the studs 1 5 bya bolt to. Thisweight .I'I may be moved bodily. along the studs 15 bylooseningthe bolt l8; A micrometer adjustment, however, .is alsoprovided. This micrometer adjustment comprises athreaded stem is whichis studded into onset the sections of the counteri'i and locked inposition by it. Two small weights 2! are adjustably threaded on thestern it, and may be moved to obtain the final balance. By screwingthese weights against each other they may be firmly locked in position.

The free end of the arm of the lever l5 (Fig. II) is bent laterally, atright angles to its longitudinal axis and this extension is providedwith a bifurcated nose 22 which extends parallel to the longitudinalaxis. bifurcated nose 2.2, engages a V bearing in a stirrup 2'4connected, by means of a connecting rod 25, to a similar stirrup itwhich engages a pivot 21 fixed in" an angularly extending arm 28 of apendulum 2 9. pivot 30, is roclzingly mounted bearings 31 inafulcrumbracket 32 secured and positioned, by means of a screw 33 and a pin to awall of an indicator casing 555. The casing 35 surmounts a housingiifiwhich rests upon a ledge of the base plate Land is secured thereto bymeans of a plurality of screws 31.

Also fastened to the base plate Hi, spaced from but parallel to thefulcrum frame 1 l, is a similar through shorter fulcrum frame which, bymeans of bearings 39 in its upper ends, supports fulcrum pivots 4B of alever il. This lever, in its plan view, is substantially U-shaped, oneof the arms of the u being provided with an angularly extending arm 42(Fig. 11) having a bifurcated nose 43 in which a pivot M is fixed. Thepivot 44 engages the lower stirrup iii of a connecting rod 46 an upperstirrup 41 of which engages a pivot 48 in a pendulum 4d. The pendulum 49is 50 on a suitable A pivot 7.3, seated in the.

This pendulum, by means of abearing in a bracket 5| similar to andfastened, like the bracket 32, to one of the walls of the indicatorcasing 35.

The pendulums 29 and 49 are provided with pendulum weights 29', 49' andindicators 52 and 53 respectively.

tending through is askeleton frame 14 in apertures in spaced arms of avertically positioned supporting frame 82. The lower ends of these armsof the supporting frame 82, by means of apertures therein, engage theends of a pin through the center of a The upper end of this link, whichis extending whose upper end of a helical tension spring 88 is hooked.The upper end of this spring engages an aperture in an extending bracket89 which is adjustably fastened to a rod 90. This rod similarly to therod 8? is fastened to the frame 74 in spaced relation to the rod 81 onthe longitudinal axis of this frame member 14. The purpose of the spring88 is to obviate lost motion of the linkage. The lower end of the link84 pivotally engages one end of a short link These indicators cooperatewith it laterally extending pivot 92. pivot as well as the edge of isalso provided with a The edge of this For the purpose of holding thearticle to be sted, for example a connecting rod lengths of connectingrods. The lower ends of the rods 8'! is supported on the bracket 96.connecting rod is then placed in shown in Fig.

This master position as I. The counterbalance weights l1 areapproximately in registration With the zero indicia on the chart 56. Thefinal, fine adjustment is made by moving the micrometer weights this rodand the location of'its' center of gravity is exactly the same as thatof the master'rod, forces of the same magnitude action the-pendulums:and: the. indicators 52" and 53Twill: again point" to the. zero. indiciain the series 54ar1d155: on the. chart 56'. When a connecting rodisplaced on the support 93' in which the'center of gravity is notcorrectlylocated, i. e., one end is heavier than the corresponding endof 'the'masterrod, the lever. supporting that end will rock through agreater angle until the additional weight is counterbalanced by thependulum. If, for example, the crank-shaft end is heavier, the pendulumweight 29 will move upwardly through a greater angle and the'indicator52' will to an indicium on the plus'side or the series of indicia 5 ofthe chart 56. Since the-graduations-in' the'series 54--55"arecalibrated, the operator" will instantly; observe the numerical value ofthe weight of that end of the connecting rod, and the indicator 53' willshow a deficiency of weight on the minus side of the series of indicia55 on the chart if-the total weight ofthe rod is. correct.

When the levers l5 and 4!, upon the application of aconnecting rod onthe support 93, rock through different angles away from their normalbalance position.the;positions of the.pivots 69 and in relative toeachother have change. To compensate for this to substantially preventithischange in the dis tance between these pivots, so that the pivots 69 and.S2.will not ,bind in their bearings the vertical upwardly extendingframe 82, in which the pivot 82 is fixed,.together with the link-likeframe 18 forms substantially a Scott ,Russell." straight linemotionlinkage in which theusual sliding block is replaced by a, Wattstraight linemowhich. comprisesthe links 85, 9| to the. center of. endor the frame. 82. ispivotally connected.-. This mechanism compensates.for. any change inthe, distancebetween the pivots 69and 92.

The. embodiment of the invention herein shown and describedistoberegarded as only, and. itis to berunderstood that the invention-issusceptible to variation, modification and. change withinthe spiritandscope of the,sub-- joined claims Having described my; invention, Iclaim:

1. In a device-ottheclass=described, in. comeination, a'pair or levers;a pairof force counters balancing and force indicating means, one -01said pairof forcecounterbalancing and indicating meansbeing .operativelyconnected said pair or levers and the otherv of said pair of. forcecounterbalancing and indicating means being operatively. connected-totheotherof said; pair of levers, one of said pair of levers being rockinglysupported "in a plane below the planer of rocking support-oi the otherofsaid-pairs of levers, means on'tle upper one ofsaid levers forsupporting one end of an'articleof'which the center of gravity is to betested and av straightline motion linkage pivotallymounted on the lowerone of said levers for supporting'the oppoe site end-oi such article andeach or said forceindicating means being adapted to indicate thecondition of balance of that one ofsaid pair of. levers to which it isconnected.

2. In a device of the class described;.in-combination, a pair ofbalancing aid pair levers, a pair of force counterand force indicatingmeans, each of of said force counterbalancing and point 1 a tendency totendency and.

which the lower illustrative means for balancing indicating means beingoperatively connected to oneof'said' pair'of levers, one of said pair oflevers being' rockingly"supported:in a plane below the plane or rockingsupport of the other of said pair of levers, means on theupper one ofsaid levers forsupporting one end of an article of which the center ofgravity is to be tested and a straight line motion linkage pivotallymounted on the lower one of said levers and extendin into the plane of'rocking'support of the upper one of said levers for supporting theopposite end of such article and'each of said force indicating meansbeing adapted to indicate the condition of balance of that one of saidpair of levers to which it is connected.

3. In a device of the class described, in combination; a pair "of levershaving fulcrums, means for supporting said levers on such fulcrums,

said levers about such fulcrums and said levers being in substantialparallel relation when inbalanced condition, a counterbalancingmechanism and associated indicating means operatively connected to eachof said pair of levers, means associated with each of said levers forsupporting the opposite ends of an elongated article to be tested onsaid device, said supporting means being correctly spaced when suchlevers arein such substantial parallel relation andsaid supporting meansincluding means for substantially maintaining such correct spacingwhensaid levers assume a nonparallel relation.

4. In a device ofthe class described, in combination, a pair of'levershaving fulcrums, means for supporting said levers on such fulcrums,means for balancing said levers about such fulcrums and said. leversbeing in substantial parallel relation when in balanced condition, acounterbalancing mechanism and associated indicating means operativelyconnected to each of said pair of levers, means associated with each ofsaid levers for supporting the opposite ends of an elongated article,said supporting means being correctly spaced when such levers are insuch substantial parallel relation and said supporting means including astraight line motion linkage for substantially maintaining such correctspacing when said levers assume a non-parallel relation.

In a device of the class described, in com bination, apair of leversrockably supported to oscillate in substantial parallelism when thedevice is in balance, one of said pair of levers being supported in aplanebelowthe plane of support or the other of said pair of levers, aforce counten balancing, pendulum and balance indicating meansoperatively connectedto each of said pair of levers, a vertical. iramepivotally connected to the lower one of said pair of levers andextending into the plane of the upper one of said pair of levers, meansconnected to the upper end of said frame for supporting one end or anelongated article, meansconnected to the upper one of said pair oflevers for supporti the other end of such article and means comprising aplurality of links for imparting movement to the upper.

end of said vertical frame auxiliary to the movement of that oneof saidpair or levers to which the frame is pivotally connected tosubstantially compensate for an out-unbalance. condition or said pair"of levers.

6; Ina, device of the class: described, in com bination, a pair oflevers of theifirst order rockably supported to assume a parallelrelation when the device is in balance and to assume a nonparellelrelation when the device is out of balance, one of said pair of leverssupport of the other of'said levers, a pivot in the upper end of saidframe, a plate having be rings for engaging pivot in the upper of saidpair of levers and said pivot in the upper end of said frame and meanson said plate for positioning and supporting such 7. A device forelongated article.

lever, a link-like member dependingly pivoted means extending downwardlyfrom said horizontally posi tioned frame and rigidly connected theretoand cle support pivotally supported on the upper end of said verticallypositioned frame first lever so that each end of said elongated articlesupport independently partakes of the movement of one of said levers,said vertically positioned frame, said link-like member and saidplurality of links forming means whereby the supporting such elongatedarticle and means on each of said levers for counterbalancing the deadWeight of such elongated article, said plate and said frame.

said vertically plate for posisaid pivot in said upper lever oscillatethrough arcs of un- HALVOR O. HEM.

